zimmerman



Nov. 3, 1942.

A H. w. ZIMMERMAN v Re. 22,219

TORQUE MEASURING WRENCH y Y riginal Filed may 51. 193s 5 Shepts-S'heet 1 Nov. 3`, 1942.

fH.` W. ZIMMERMAN TORQUEMEASURING WRENCH origina; Filed may :5221938 v s Smets-sheet 2 MIIIIIHI-IIIIIIIIIIIH'IIlih.

Zllll!! llllllllllHZE W l Now 3, 1942.`

H. w. ZIMMERMAN Re. 22,219 TORQUE MEASUR-ING WRENCHV V 3 Sheets-Sheet .'5

Original Filed May 31, 1938 Remue-'d Nov. 3, 1942 TOBQUE MEASURITG WRENCH Herman W. Zimmerman, North Newington,

Conn., assigner, by menne assignments, to Automotive Maintenance Yachinery Co., North Chicago. lli.. a corporation of Illinois l Original No. 2,269,503, dated January 13, 1942, Serial No. 210,869, May 3l, 1938. Application for reissue January 24, 1942, Serial No. 428,142

'31 claims.

My invention relates to torque measuring wrenches adaptedffor determining the force or torque appliedtherethrough to work such as nuts, bolts. studs and the like. g

One of the objects of my invention is to provide an improved torque measuring wrench which is of a simple, inexpensive, rugged and compact construction; and which is adapted to eiilciently perform its torque measuring and indicating functions with precision at all times-and under all normal conditions ci use.

` Another object is to provide an improved indicating mechanism for torque measuring wrenches which is of a very simple and inexpensive construction, embodies but few operating parts, isdurabie and capable o! withstanding rough usage, is adapted to accurately record the force or torque applied through the wrench, and is so constructed and arranged that it may be readily and quickly assembled as a complete unit with the remainder oi' the wrench structure.

A further Objectis to provide a torque measuring wrench that is well adapted for -uniiorm reproduction in. large quantities for production purposes. the arrangement being such that but few wrench parts are employed, which parts are of a character adapted for accurate reproduction' in large quantities, and which may be assembled withoutlspecial selection in wrenches having the same power rating and having the ability todo the same work with uniformity in action and accuracy. The wrench parts are so constructed that corresponding parts of' different wrenchesl having the same power rating may be interchanged without variation in the intended operation and power rating o! the wrenches.

' Other objects are to provide a wrench ofthe foregoing character having a pair ol relatively movable parts with an elongated spring member engaged at its opposite ends with such parts and yieldably` opposing relative movement therebetween, the arrangement being such that the connections between the movable parts and between Fluch partsy and the spring member are oi precif vf-cion character adapted to be accurately reprof l"duced in successive wrenches, enabling the conncted parts 'of ditlerent wrenches to be interf changed without impairing the intended accuracy 'of thewrench; to'provide an improved connecl tion betweenrel'ativelv movable wrench parts and 'the gage mechanism -by which the gage mech- "anismmaybereadilyandeasilyappliedandreanyottheoth'er` moved without detachment oi wrench parte, and'which is o t a character adapted to 'absorb shocks experienced intheiiseoithe (Ci. 28E-1) `wren ch, thereby tending to minimize injury to the gage mechanism; to provide means for insuring return of the gage mechanism to its normal position of rest.notwithstanding play or operator may readily determine from various angles when. the desired pressure is applied to the` work; to provide a wrench that may be readily and easily assembled, disassembled and used" by an unskilled workman; and to provide a simple and inexpensive, out eicient, ratchet unit that may be readily and detachably applied to the wrench.

Other objects and advantages will become apparent asthis description progresses and by reference to the drawings wherein- Figure 1 is a top plan view oi' one wrench embodying my invention:

Fig. 2 is an` enlarged view of the head portion of the wrench shown in Fig. 1, the top cover being removed to illustrate the internal wrench parts; L

Fig. 3 is a longitudinal section taken substantially on the line 3-3 oi Fig. 2;

Fig. 4 is an enlarged vertical sectional view of `the gage mechanism and the parts by which it is associated with the remainder of the wrench structure;

Fig. 5 is a horizontal sectional view'taken substantially at the position indicated by the line B-i in Fig.y 4;

form of Fig. 6 is a detail sectional viewtaken substanaannames-601mm v Fig. 'I is a horizontal sectional view taken substantially on line 1-1 o1 Fig. 4; Fig.8 is a. vertical sectional view of another 40 form of gage mechanism that may be employed in a wrench embodying my invention;

Fig. 9 is a top plan view of the structure shown in Fig. 8, a portion of the upper part of' such structure -being shown in section;

Fig. `10 is a diagrammatic outline view of the .dial structure shown in Figs. 8 and 9. and by which the relationship of the top and side dial markings is betterv shown;

Fig. 1l is `a. tragmental view, partially in section, of a ratchet iorm of wrench embodying my invention: f l Pig. 12 is a top plan view. Partially in' section,` o! another iorm o'i gage mechanism emmy invention; and Pigs. 13 and 14 are top plan views of addiof the head 2U.

tional forms of gag'e mechanism embodying my invention. Y

'I'he wrench shown in Figs. 1 to 7, inclusive, comprises a hollow head portion 2|) having a top cover 2| detachably secured thereto by a plurality of screws 22 that engage threaded openings 23 in bossesy 24 formed on the inner wall The head 2li is provided with a rearwardly extending lintegral handle 25 having a grip portion 2lia adapted to receive and,

position vthe hand of an operator in the use of of the wrench head 2li may be provided with a socket (not shown) in which a separate handlepiece is secui ed.

The head 20 rotatably `supports a work-engaging member 26. The work-engaging member 26'is provided with an annular body portion 21 having reduced annular-` bearings 28 extending axially from the opposite sides thereof for rotatable reception in aligned openings 29 formed in adjacent and opposite, thickened wall portions 30 at the-forward end ofthe head 20. friction bearings 3| are mounted in the openings 29` whereby the work-engaging member 26 is mounted for rotation relative to the head 29 CII the wrench. If desired,.however, the rear end with a minimum of friction. The forward, inner end wall of the head is roundedy comple-l mentally to the work-engaging body 21, which is of less diameter than thehead" end wall, thereby providing a peripheral space 2lib between these parts. The inner ends of the aligned head openings 29 are surrounded by narrow annular seat portions 32 against which the outer edges o the opposite faces of the work-engaging body 21 engage. i By such an arrangement, together with the lanti-friction bearingsv 3|, the head 20 and work-engaging member 26 are adapted for relative rotation with a minimum of friction.

Relative "rotation between the head 20 and work-engaging member 26 is yieldably opposed by an elongated spring bar 33 which is connected at one end to ther head 20 and at its other end .as shownin Fig. 3. In'r this way, productionof large quantities of wrenches is facilitated in that all work-engaging members and their arms may be similarly formed to receive similarly formed spring bars in exactly the same way.

The rear end of the spring bar 33 is rotatably connected to the rear end of the head 20 in the following manner: The bottom wall 20* of the -head and the cover 2| thereofI are provided, at

the rear of the head 20, with aligned openings 31 in which are received thimble-like anti-friction bearing members 38 which arev so positioned that their open ends extend inwardly of the head 20. Connection between-the spring bar 33 and the head is directly accomplished by a cylindrical coupling member 39 which is provided with a transverse opening 40 in which the end of the bar `33 is freely received.` The walls of the opening 40 flare or diverge outward'g.' at both ends from the axis of the coupling member so that the contact between such coupling member and the spring bar is substantially only at and onthe axis of the coupling member. The coupling member 39 is provided at its opposite ends with axial journals 4i which are snugly and rotatably received in the bearings 38, the arrangement being such that the connection be- L tween the head 2Dand the spring bar 33 is a rotatable one. This connection permits rotation between the coupling member 39 and the head 2U, as well as limited rock movement between the bar 33 and the Vcoupling member" 39, so that the bar 33 will at all times be free to flex normally during operation without any cramping action or any `other restriction which may tend to set up conditions causing the wrench to regis-ter abnormal forces. v n

I have found that a cylindrical spring bar is Well adapted for the attainment o f the purposes of my invention. ,f Spring bars of this character may be formed yand tempered quite accurately so that successive spring bars having the same power rating may be formed with but a slightY to the member 26. More particularly, the work engaging member 26 is provided with a rearwardly extending rigid arm 34 disposed at right angles to the axis of rotation of the member 26, which arm has a web-shaped central portion that reduces the weight Yof the arm without impairing its strength and rigidity. It is desired that the arm 34 'be sutliciently rigid to prevent flexing of the same in the use of the wrench and, to that end, it is first formedto the shape shown and then hardened in any suitable fashion.

By forming the arm 34 as stated, itis provldedwith a full section rear end portion `34a of predetermined size. This arm` portion 34 is provided with an opening 35 extending substan- 4tially parallel with the longitudinal medianline of the arm 34, which opening is adapted to receivethe forward end of the spring bar 33. The

opening 35' is drilled entirely longitudinallyL through the full section end 24"*` of the arm and until. it breaks through the rear end thereof into the` web portion providing air release ports 36 at the juncture with, the web portion of the an axialopening 21e.

nect the wrench and the work with the axes of arm. In this way, the openingis readily formed to a predetermined length and diameter. The iit between the end of the spring bar 33 and the arm openingy 35 is sumciently close to pro-v vide a tight pressed fit between these parts, and by providing the openings 36 at the end of the arm opening. I am able to force the forward end of the spring bar 33 entirely home within` the opening and until it abuts the rear end thereof and immaterial percentage of error.

The work-engaging body 21 provided with adapted to non-rotatably anddetachably receive a work-engaging adapter (not shown) of any suitable and well-known form.v Preferably.,` I employ a work adapter which is. arrangedto conthe work and the work-engaging body 21 co- `inciding'; however, where the work is difiicultof access, different and off-center types of adapters may be employed in order tov engage the wrench with the work. In the latter case, for accurate results, the hand grip portion 25El of the wrench handle should be grasped in a uniform manner in order to insure proper pressure indications when working on successive, related piecesfofA work which. are to be set up to` the same pressure.

.When the work-engaging member 26 is ,en-

gaged with thefwo'rk and the hardle 25 is grasped'- and moved in a clockwise direction (as viewed in Fig. l), the' head .20, work-engaging member 26 and the work, through the couplingl afforded -by the spring bar 33, move together as a unit until the work is tightened to a point wherein the initial tension ofthe spring bar 33 is over-V come. As` this happens and rotation of the Hwrench handle 25 is continued, the sprlngbar- 33 will be exed, permittingrelative rotation between the head 20- and the, memberi 26, the extent This opening is, prefer-` ably, of rectangular shape or any other shape` sazia of which relativerotation depends upon the pressure applied and the extent of exing of-the spring bar 33. Therefore, by measuring the extent of this relative rotation, I am able to determine the amount of force or torque applied through the wrench to the work, and one form of gage mechanism well adapted to accomplishl this will now be described.

The gage structure shown in Figs. l, and 3 to 7, inclusive, is detachably supported by the cover-plate 2|. The `gage structure includes a disc-like body member 42 having an axial depending annular part 43 which is'reely received in an opening 44 in the cover-plate 2|; The plate 42 (Fig. 4) is detachably secured to the cover 2| by screws 45 which freely pass through slightly enlarged openings 42e in the plate 42 and engage threaded openings 2li* in the cover 2|. The foregoing arrangement provides some play in the unsecured gage mounting so that the gage unit may be shifted somewhat'i'or proper connection with the wrench actuating means hereinafter' described. When the parts are properly connected, the screws 45 are tightened, holding the gage in a predetermined position.

The gage structure takes the form ci a selfcontained unit, and it further includes a frustoconical dial 46 formed oi' relatively thin and light-weight material such as Celluloid or the like. The top of the dial is provided with a metallic anchor member 41 having a depending annular part 41*i adapted to be snugly received in a similarly shaped axial opening 48a formed in the upper end of a rotatable dial support 48, The upper end of, the dial support 48 is provided with an enlarged head portion 4|!b providing with the anchor member 41 an adequate support for the dial 46. The dial 46 is detachably secured to its support 48 by a screw 49 passing through the anchorfpiece 41 and engaging a threaded opening in the support 48.

The dial support 48 is adapted to seat and rotate upon the top of the body member 42, and rotation is imparted tolit through a pinion 50 on the lower end of a shaft axially secured to the lower end of the support 48. The shaft 5| is rotatably supported in an opening in the body i member 42, the lower end of which opening is enlarged to provide a recess 52 in which the pinion 58 is received.

The pinion 58 is adapted to be actuated by a rack bar 53 which is also located in the recess ,52. The rack bar 53 and pinion 58 are retained in operative relation by a comparatively thin plate 54 secured to the bottom ot thepart 48 by a plurality of screws 55. Therack bar 58 carries a centrally disposed and depending pin 56 which projects downwardly through an elonhead 28 and the work-engaging member 26 rock relatively, the gage mechanism moves relatively to the coupling member 51, thereby imparting movement to the pin 56 and the rack bar 58, in turn, rotating pinion 58, dial support 48 and dial 46. The forked engagement between the coupling member 51 and pin 56 accommodates arcuate movement of these parts during their relative movement.

Wrenches of this character are subjectedl at times, to severe shocks and movements which, unless otherwise guarded against, will tend to injure gear-type gage mechanisms. For exam-f ple,v if, `in tightening a bolt, stud or other piece of work, breakage of the work should occur while a considerable pressure is being applied to the work, the instantaneous release and reverse actuation of the gage mechanism under the existing tension condition would tend to .strip the gears of the gage mechanism. Also, in loosening a piece of work, considerable pressure may be required to move the work and the initial movement, once it is started, may be quite sudden so that the gage mechanism is subjected to shock and movementlmuch like that which occurs when v a piece of work breaks, In carrying out my invention, I yavoid injury to the gage mechanism gatedslot 51 formed in the platey 54; By moving the rack bar 53 back and forth, the pinion 58 is rotated, in turn rotating the dial support 48 and the dial 46..V

Movementl of the sliding rack bar 53 by the relative rock movement of the wrench parts.28

, and 25 is accomplished through a flat, barlike coupling member 51, the forward end 51" of whichlFigs. 2 and 3) is of enlarged rectangular-like shape and is secured to the rear end of the work-engaging arm 84 by screws 58. The

coupling member is further provided with an elongated narrow stem part 51Ahaving a fork 51 at its'rear end. The coupling member stem bar 58. With this' arrangement, as the wrench cor ' 51 is of such length. that its fork 51h is aligned y with and receives the pin 56 carried by the rack under the foregoing conditions by employing a gage coupling member 51 which is adapted to flex and absorb the shocks that are experienced. under the conditions in question. Speciiicaily, the coupling member 51 is formed of a high'- grade steel material and the coupling ann 51a thereof is of such width that it will tend to flex when a predetermined pressure is applied* t'o the forked end 51 thereof; but the pressure required to'fiex the arm 51b is greater than any pressure that will be exerted on the member 51 in the Vnormal relative rotation of the wrench parts.

In other words, the pressure normally exerted on the member 51 is only thatrequired to move the sliding rack bar 53, pinion 58 and the dial unit, which pressure is necessarily very much less than that which would be suddenly exerted on the arm by the spring barA 33 in case of abruptrelease of the parts with the spring bar under any considerable tension.

The side wall of the gage dial 46.(Fig. 3) is provided with a scale 68 graduated from zero in opposite directions to indicate, preferably, relative movement of the parts and pressure applied to the wrench in terms of inch-pounds pressure. The dial -is enclosed by a removable and rotatably adjustable cover 6| having a dome-shaped ytop wall 6|* and a depending annular` side wall 6|". The top Wall 6| of the cover is provided with a sector-shaped window 62 near its periphery through which theangularly disposed scale 68 ofthedial 46 may readily be observed.

The cover 6| is detachably secured to the gage body member 42.4 Specically. the cover side wall is provided near its bottom edge with an internal annular groove 63. The peripheral edge of the lgage body 42 is provided with a plurality of apertures in which spring-pressed balls 64 are received, the arrangement being such that y the cover 6| ls adapted to be snapped upon the gage plate 42 with the balls 64 received in the grooves 5,3. In this way, outward accidental displacement of the cover is avoided and such cover maybe rotated to any positionrelative to the dialy where it will be held by the tension of the spring-pressedballs 64. The cover 6| may be.

removed intentionally by applying sufficient pres sure to its lower edge to overcome the tension of the spring-pressed balls il.

. It will be appreciated that the operator, in

using the wrench, may assume various positions in which he must yobserve the dial 46 from vari.

ous angles. To facilitate the reading of the dial scalef ill under these conditions, the coverwindow 82", which is covered by a transparent member 65, is located in the incined wall surface of the dome-shaped op 6|* of the cover. This wall i surface extends in a direction substantially parallel with the slanting side wall of the dial 46 on which the scale 60 is located. With such an arrangement, the operator may read the dial scale 60 at various angles from beyond the vertical to below the horizontalV and from the opposite sides of the wrench. 'I'he transparent window 65 is provided with a centrally disposed indicating the work-engaging member may be first applied to the wrench head and it is secured in place therein merely by applying and securing the liner 66 which is adapted to register with the graduations of the. dial scale 60. In use, for example, the cover indicatingline 88 may coincide with a zero point on the scale 60 when the wrench is at rest; and, if it is desired to set up a piece of work to a desired pressure, such pressure will have been reached when the dial I6` is rotated to an extent to register that pressure indication d, on the dial I6 with the indicating line G6. Or, if

desired, the cover 6I maybe rotated relative to the dial, in the at-rest position of the wrench,

`vuntil its indicating line 66 coincides with a certain pressure graduation on the dial I6 and,

"when suiiicient pressure is applied to the wrench to rotate the dial to bring its zero scale marking into coincidence with the line i6, the intended pressure has been applied.

Gage mechanism of the foregoing character v rest position.

To the foregoing end, vone side of the lower portion of the dial support ,Il is provided with a concave cut-out l1 forming point contacts il that are engaged by an elongated spring member 69 havingits opposite ends supported by posts `l0V on the opposite sides o1 the member Il. The

posts Il are so located and the spring l! is so yshaped that the latter yengages the points n y proper tit of the parts without the necessity of` specially tting and testing individual parts and ymust necessarily be sensitive and operate with cover plate 2l. The gage'mechanism may be readily applied as a unit, it being only necessary to insert the part I3 in the cover opening Il at a position wherein the screws will engage the openings 2P, in which position the depending rack bar pin 56 will be received in the forked end 51u of the coupling member 51. After the plate 42 with its dial support 4B are thus secured, the dial 46 may be secured to the support 48 and the cover 6l then snapped in place. For sake of precision in operation and also as an aid in reproduction of similarly powered and acting wrenches in large quantities, the axis of the rotatable connection between the head 2liA and work-engaging member 26, the rotatable axis of the connection between the rear end of the spring bar 33 and the head 20, and the axis o1' the gage-receiving cover opening are al1 longitudinally aligned. This facilitates assembly and wrenches. .i l

I have also found that the weight of the dial `is of importance from the standpoint of injury to gear mechanism upon sudden operations causing shocks in the use of the wrench. In other words, the lighter the dial structure, the more satisfactory it is from the foregoing standpoints. For that reason, as above stated, the dial 46 is formed of very thin and light-weight material which may be readily applied to rotatable supporting structure, as shown in Fig. 4, without the use of weight-increasing liners or supports.

It will be understood that the dial may take various shapes and may carry different indicating media such, for example, as those shown in Figs. 8l to 10 and l2 to 14. Specifically, with respect to Figs. 8 tg l0, inclusive, the gage structure illustrated is similar to that previously described except that the dial 80 is provided with a nat top 80 and a skirt 80h. extending at substantially right angles thereto. The cover 8| is similarly shaped, Abeing provided with a circular opening Il in its top and a rectangularly-shaped opening lib in its skirt, the two openings being lo under tension. With this arrangement, the dial support 4I will always be returned to its normal,

at-rest position (Fig. '1) notwithstanding any play or backlash ybetween the teeth of the slide rack bar 53 and pinion 50, due to the` fact that the spring il always tends to rotate the member 48 to its center position with both of the contact points 6B engaged as the member Il `approaches its normal, at-rest position. The springt! further tends to act as a brake in steadying the rotative movement of the dial structure in any. position thereof.

` may be colored green, the discs 8l may be yellow, l

It will be seen from the foregoing that I have i provided a highly eilicientv wrench while using but few parts in the wrench structure as a whole, including the gage mechanism.` I have also pro-` vided an arrangement which may be quickly and easily assembled and disassembled without the necessity of using any particular care. That is,

` 'top of `the dial and the squares in cated approximately 90 degrees apart.

The dial is provided with color indicia on both the top 'and skirt thereof; each color indicating a` certain pressure or a certain desired .position which the gage is to assume in order to properly set up a pleceof work. More particularly, the top of the dial is provided with a plurality of colored' discs that are adapted to coincide with the top cover opening Sie. These discs may be so arranged that in the normal, atrcst position of the wrench a white disc 82 registers with the cover opening 8|. Extending both clockwise and counterclockwise (as viewed in Fig. 10) from the white disc 82, the discs Il the discs 85 may be red, the'discs 86 may be blue,

vand the disc 81 may be black. Likewise, the side wall of the dial may be provided with aY-white area 88` adapted to coincide with the side wall cover opening Bib in the normal, at-rest position o1' the `wrench, and it may also be provided with oppositely extending rows of green areas 89, yellow areas 90, red areas 9|, blue areas 92 and a black area 93.I The arrangement of the discs on the skirt thereof is such that when `a disc ofyany particular yprovided with color, upon movement of the wrenchin eitherdirection, as to tighten or loosen the work. registers with the top coveropening Il". a similarly apex'rcoincideswith that 4of a triangularly shaped 1 mark/IN4r on the transparent-window |22 of the colored disc will register with the opening v in the. side wallof the-cover. In this way, the

operator is able to determine the pressure indi- A cated by the wrench from the various positions that he may assume in-using the wrench. I

have found dial structure of this character to be useful where the wrench is to be used for different kinds of work that is to be set up to different pressures.` Each color may indicate a certain pressure and, following instructions given as to thepressure indicated by each color, .the I workman using the wrench need only be instructed to set up one piece of work to-the yellow color, another piece to red, another to blue, etc.

Or, if desired, the cover 0l may be rotated so Fig. 11.

that its openings register with a particular color,

cover |0| is provided with a black V-shaped indicating mark |02. The slanting side wall of the dial is providedwith a plurality of inverted V-shaped color zones |03 which maybe colored similarly to the areas shown in Fig. 10, or in any other way desired. In this form, I may employ a white zone |04 which, when its apex coincides with that oi' the black Lmark |02 on the cover, indicates the normal, at-.rest or zero position of the device. Relative movement between the wrench parts results in movement vof the dial color zones relative tothe black cover mark |02 and any particular color zone may represent a predetermined-pressure condition' or` the extent to which any particular piece of work should be tightened. v

In Fig. 13 I have shown a dial arrangement shaped similarly to that of Figs. 4 and 12 but v the scale vl|| offligf.. 1 3 lis employed and the device is use The use of aA y l still further reduces. theweight of the rotating dial structure. therebyfirfurther aiding in precision ofoperation.

-At times it maybe-desirable to use a wrench of the foregoing character with av` ratchet feature and, Ifor thatv purpose; I .provide an improved form of ratchet unit that m'ayreadily be attached to and disconnected from the wrench. One form of the'unit that I employ is shown in Specifically, the ratchet structure includes a pair of ratchet lheads |30 and |3|, each of which is provided with` ratchet teethy |32 adapted to be engaged in the manner illustrated. These heads also areV provided on their outer surfaces with axial extensions |33 and |34, respectively, which are adapted to non-rotatably engage in irregularly shaped opening |35 of the workengaging member formed in a work adapter (not shorWn).' The head I3| is further provided with an axial recess |31 in which is received the enlarged head |30 of a pin or projection |30 axially carried by the head |30. A screw |39 carried by the head |3| is provided vWith areduced end portion projecting into the recess |31 where it is adapted to be engaged by the head |38"` of the pin |30, thereby limiting thegextent to which the ratchet heads n may be separated. The extent 4of thismovemen-t need only bei-slightly greater tha'nthe depth of the ratchet teethy |32 whereby the ratchet heads A may be separated in axial direction for movement of one relative to the other as-in the non-ratcheting movement oi' the ratchet structure. The

wrench structureniay besimilar to that shown in Figs'. 1 to 3,-,inclusive,v orl it may take any other -formfjsuitablemr V cp n'nection with the having diil'erent pressure indicating means. In

this form, the top cover |'|0 of the wrench is provided with a scale having a zero point and graduations extending in opposite directions pressure. The

provided with a IIS and the slanting `side wail Ill of the dial is a triangularly shaped indicating' mark |15. In the zero position of the wrench parts, the apexes l incide. If it is desired to set up a piece vof work to a point requiring the application of,'say 300 inch-pounds pressure, the cover( I is rotated in clockwise direction (as viewed in' Fig. 13) until its arrow mark ||1 coincides with the 300 mark ||0 on the scale the work is then tightened until a sufiicient pressure is exerted to cause rotation of the dial Ill in a clockwise directiontobring its indicating mark III into alignment with the cover` mark |13. Indications are'given in a similarmanner when the wrench is rotated in the opposite di-v rection, aswhen loosening the work. f I j -In Fig. 14 I have shown an indicating means similar to thatl of Fig. 13 except that a hand or pointer |20 is used instead of a dial such as shown in Figs. 4 and 13.` In this form, the outer end |20 of the vhand or pointer is V- pedland;y

`ratchet un1t f.jjn1jthefusejorthe structure. with .the ratchet! unitfensazec. lwith the work, the

weight M thezwrefric flsfcmally sufficient to move and -'h oldftliesupp ermfo'st'ratchet head in operative "engagementfwith'r the.v lower ratchet l -If the;Wlfle-is'(*being tightened. backward or counter-clockwise movement of the wrench will fresul'tjfin 5th '-r 'tchetteeth y of` theV lower ratchet head vv:the ratchet .teeth of the upper head out; offengagement therewith so of themarks m and tls eta-'1;'v

f 1l other-andrform f'sure is directly upon' the revei'sfefmovement of the-wrench, the teet normally-'move into engagement'with each unit through which presppliedto thework.; Either shank extension :"offth --r'atohet'u'nit may be connected With the wrench so set,

to l-the""wren'ch', l` whichis'an added convenience in `applyingtlije ratchet unit.l Also. the ratchet unit may be' employedf'as :an accessory Ifor other types' of wrenche'sand for ratchet operation.

for converting the same It will be seen Afrom the foregoing that I vhave provided .averyvv simple and inexpensive ratchet. structure which embodies but few parts, none of which is of a charinvention is not onlyacter likely to get outv of working condition in the ordinary use of the wrench.' I believe that the operation and .advantages of my`iru7ention willbe apparentfromthe foregoing description. The wrench embodying my simple in construction but it jisinexpensive to manufacture. Atfthe'same time.' the wrench is adapted to accuratelymeasure d in-thesame way as that of Fig. 13.- hand |20 instead of a complete dial -|3|i or in a similar opening ber rotatably mounted in sociating one of said members ing means adapted for measuring relative movebar is freely received, said said bearing elements.

' with v top `and bottom walls aligned openings the pressure applied. The parts of the wrench are such that they may be accurately reproduced and stocked so that successive wrenches may be assembled from parts indiscriminately` Y selected, thereby providing a wrench capable of satisfactory manufacture on a large production basis. Individual selection, testing and adjusting oi wrenches is not necessary.

1. A torque measuring wrench comprising an elongated head member, a work-engaging memsaid head member at the front end thereof and having a part exteriorly accessible-for connection with the work, a rigid arm on said work-engaging member extending rearwardly within said head member and having a longitudinal opening of predetermined size leading from its rear end toward the axis oi' rotation of said work-engaging member and at right angles thereto, said arm also having at least one `vent opening connecting the inner end of said opening to spring bar in said head member and having one end shaped similarly to said arm opening and iltted therein so thatsuch -bar serves as the spie means opposing relative movement between said members. and means i'or aswith an indicatment between said members in a manner to indicate pressure applied to the work.

-2. A torque measuring wrench adapted for use with means for indicatingA the force applied by the wrench to the work comprising an elongated y head member having top, andA bottom walls, a

work-engaging member rotatably mounted in the top and bottom walls of said head member, a spring bar having one` end secured to said workengaging mem-ber, and a connection between the atmosphere, an elongated end extends sub-4 y stantially to the inner end of said arm opening, means connecting the-other end of said spring `bar to said head member. so that said spring bar f stantially on the axis oiI said head member other end of said spring bar and said head member` whereby said spring bar opposes relative movement of said members, said connection including a bar-supporting member having an openingtherein iny which the end ofsaid spring head member having top and bottom walls extending substantially rotation of said work aligned openings infthe thereof with their axes Parallel with the axis o'i said head member openings, and a pair of op'positely extending and axially` aligned bearing members on said bar-supporting member and extending at substantially right angles, tosaid.

bar-receiving opening and rotatably received in 3.. A torque measuring wrench` adapted for use means for indicating Vthe force applied by the wrench to the work comprising an elongated head member yhaving top and bottom walls, a work-engaging member rotatably mounted in the spring bar having one end secured to, said workengaging member, and -a connection between the other end of said/spring bar and said head member whereby ysaid spring bar opposes relative movement of said members, said connection incliiding` a bar-supporting member having an opening therein in whichithe end of -said spring oi' said head member, a

bar is freely received. said head member having in the thereof with their aies parallel with the' axis oi top and bottom walls extending substantially rotation 0l' Said Workengaging member,

thimble-shaped anti-friction bearing elements mounted in said head member openings with. their open ends extending in wardly 'toward each other, and axially aligned bearing members on said bar-supporting member and rotatably received in said bearing elements.

4. A torque measuring wrench adapted for use with means for indicating the force applied by the wrench to the work comprising a head member-having top and bottom walls,'a work-engaging member rotatably mounted in the top and bottom walls of said head member, a spring bar having one end secured to said work-engaging member, and a connection between the other end of said spring bar and said head member whereby said spring bar opposes relative `movement of -said members, said connection including a barsupporting member having opposed and axially alignedI bearing members, said bar-*supporting member also having a bar-receiving opening extending therethrough at substantially right angles to the axis of saidbearing members, the opposite end walls,` of which opening converge inwardly towardithe mid-portion of such opening so that said bar is normally engaged therein subsaid bearing members, said bearing members being rotatably carried by the top and bottom walls of saidmhead member.

SLA torque measuring wrench comprising a head member having top and bottom walls, said head member having aligned circular openings at the forward -end thereof in said top and bottom walls, aligned circular openings at the rear end thereof in said top and bottom walls and an intermediate opening in said top wall, all of said ing relative movement between said head and work-.engaging members, lmechanism indicating the pressure applied to the work including a part ntting vin said intermediate opening, operating means supported by saidmechanism part, coupling means operably connecting said work-engaging member with said operating means, said rotatably mounted parts being so constructed and arranged and all said, openings vso aligned that Vsaid, coupling means and operating means are merely by moving said mecha-i operably engaged nism part to one predetermined position relative to said couplingmeans and inserting it axially within said intermediate opening.

,6. A torque measuring wrench comprising a pair of members rockably connected together, means by which one of said members may be engaged with the work, means on the other of said members by which it may be moved, spring means yieldably opposing rock movement between said members, one of said members 7. A torque measuring wrench comprising a pair oi members mounted in said -rear. openings, V whereby said bar serves as the sole means oppos-v gage mechanism carried by mskably connected together.

means by which one of said members may be engaged with the work,means on the other of said members by which` it may be moved, spring means yieldably opposing rock movement between said members, gage mechanism carried by said other member and including an operating part movable back and forth, andV a coupling member connected at one end to said one member and having its other end free and constructed to receive said operating part for imparting motion thereto as said members rock relatively, said coupling member being adapted to flex when sub- Jected to pressure greater thanthat required to impart motion to said operating part, whereby4 shocks caused by release of the wrench when said spring means is under operating tension is absorbed by said arm, preventing injury to the operating parts of the gage mechanism.

A torque measuring wrench comprising a l pair of members rockably connected together,.

means bywhlch one of said members may be engaged with the work, means on the other of said members by which it may bemoved, spring means yieldably opposing rock movement between said members, pressure indicating means carried by said other member and including a rotatable indicator, gear means for rotating said indicator, a member slidable back and forth for operating said gear means, and a coupling member connected at one end to said one member and having its other end free and of suitable shape for receiving said slidable member and for actuating the latter upon relative rock movement of said members, said coupling member being constructed and arranged to iler; when subjected to pressures greater than` the pressure exerted therethrough to actuate said vslidable member whereby shock caused by release of the wrench parts when they are subjected to high workapplled pressures is absorbed by said coupling member, preventing injury oi said indicating means.

9. A torque measuring wrench adapted for use with means for indicating the :torce applied by the wrench to the work comprising, a head memf ber, a work-engaging member rotatably mounted in said head member, a spring bar having one end secured to said work-engaging member and a connection between the other end of said spring bar and said head member whereby said spring bar opposes relative movement of said members, said connection including a supporting x member having bearing means rotatably supported in said head member, said supporting member also having an opening extending therethrough at substantially right angles to the axis of said bearing means, and the wall of said openlng converging' inwardly in such a ,manner as to provide a substantially line contact with said spring bar.

1G. i torque measuring wrench comprising a head member having top and bottom walls, said head member having aligned circular openings at the forward end thereof in said top-and bottom walls, aligned circular openings ai'. the rear end-of said head member in said top and bottom walls and an intermediate opening in said top wall, a work-engaging member having parts ro- 'tatably mounted in said forward openins, a

spring bar connected at one end to said work-engaging member, a connection between the other end of said bar and said head member including a member having parts rotatably mounted in said rear openings, said intermediate opening being constructed and arranged to receive an operating part oi' a pressure indicating mechanism, and 'means carried by said work-engaging member and adapted to be operably engaged with the operating part oi the indicatingmechanism merely by axial` insertion of such mechanism part in said intermediate opening from a certain position relative thereto.

l1. A torque measuring wrench comprising a pair of members rockably connected together, means by which one of said members may be engaged with the work, means 'on the. other of said members by which it fmay be moved, spring means yieldably opposing rock movement between said members, gage mechanism carried by said other member, a pairof operating parts,y one carried bysaid work-engaging member and the other by| said gageY mechanism, for operating said gage mechanism upon relative rock movement of said members, .one of said parts being adapted to iiex when subjected to pressure greater than that required to impart motion to the other of said parts, whereby shocks lcaused by release of the wrench when said .spring means is under operatingtension are absorbed by said operating parts thereby preventing injury to the gage mechanism.

12. A torque measuring wrench comprising a pair of members rockably connected together,

means by which one of said members may be operably engaged with the work, means on the other of said members by which it maybe moved, spring means yieldably opposing relative movement of said members, gage mechanism carried by one of said members and including an operating part movable back and forth, a coupling part operably associated with the other o said members, one oi said parts being constructed and arranged for connection with the other part bar connected at one end tov and extending reartvardly from said work-engaging member, a connection between the other end of said bar and said head member including a member rotatably ,mounted in said head member, pressure indicating means including a depending operating part adapted to be received in said opening, and

. means movable upon relative movement of said work-engaging and head members and flexing of said spring bar, said means and said operating part being so relatively constructed and arranged that such means is'operably engaged with said operating part -merely by axial insertion of said part of the gage mechanism in said opening at a certain rotary position relative thereto.

i4. A torque measuring wrench comprising, a pair oi' members rockablyconnected together, one oi said members being adapted to be connected with the work and the'other of said members being adapted to have a turning force appli-ed thereto, 'a normally straight spring bar member yieldably opposing relative r'ock movement of said rockable members, indicator means carried by one of the members, and flexible means carried yby another of themembers and being Y `cooperable with said indicator means for effecti member yieldably opposing relative rocicmove-I ment Aof said rockable members, indicator means' carried by one of said members and including an operating-part, and` flexible coupling means carried by another of said members and, having an element adapted to be operably connectedv with said operating-part for eifecting an-indication Aof the force applied to the work, said exible coupling means having relatively, "greater exibility than said springbar member in the direction of bending of said spring bar member.

16. A torque measuring Wrench comprising a pair of members rockably connected. together,

one of said members being adapted to be con-` nected with the Work and the other of said members being adapted to have a turning force applied thereto, a normally straight` spring bar member yieldably opposing relative ,rock `m'ove ment of said rockable members, indicator mechanism carried by'one'of the members and including an operating-part movable back and forth in the direction in which said spring mem- 'berbends as said members rock relatively, and

ilexible coupling means carried by another of the members and having an element adapted to be operably connected with said operating-part for moving thel latter back and forth as said members rock relatively, said flexible coupling means having relatively greater exibility than said spring bar member in the direction of bending of said spring bar member.

17. A torque measuring wrench comprising a pair of members rockably connected together, one of said members being adapted to be connected with the work and the other of said applied thereto, anormally straight spring bar member carried.` by one of said rockable members and being operably engaged with the other of said rockable members and being adapted to flex as said rockable members rock relatively, indicator mechanism carried by one of said"rockab1yconnected members and including an oscillatable indicator-operating part, and means carried by another of said members for coupling it lto said indicator-operating part, said means including members being adapted to have a turning` force actuated toy apply a turning force to the work.`

a normally' straight flexible spring bar member carried by one of said rockable members and "being operatively engaged with the other of said rockable members so as to yieldingly. oppose relative rock; movement of said rockable members, force indicating means carried by one o f said rockable members and including an indicater-operating part, and means forcoupling said indicator-operating part to one of the other of said members, said means including an elastic element vhaving relatively greater ilexibility than said spring bar member in the direction of bending of said spring bar member, wherebyV when said wrench is in use said indicating means will be actuated to` indicate the force applied to the Work upon relative rock movement of said rock members and said flexible element tends to absorb the shock on said indicating means in the event of a sudden release of the force being transmitted through the wrench.

`19. A torque measuring wrench comprising, a

'headmemben a work-engaging member rotatably mounted with respect to said head member' and having a portion provided with a bore, said bore extending in a direction transverse to the axis. of rotation of said work-engaging member, an elongated spring bar member having one end thereof securely mounted in said bore and having its opposite end operably connected with said head rotary movement of said head member and workengaging membenand indicator means operable as said head member and work-engaging member `rotate relative to each other for indicating the force applied to the work through said mema flexible coupling'element having operative enf i `gagement with said indicator-operating part, said coupling element having relatively greater flexibility than said spring bar member in the direc'- tion of bending of said spring bar member, whereby relative rock. movement of said rockable members imparts movement to ,said coupling element and, in turn, oscillating movement to said indicator-operating part to operate said indicator mechanism and said flexible element tends to absorb the shock on said indicator mechanism,

, member for yieldably opposing relative rotary bers and spring bar;

20. A wrenchas dened in claim 19, in which Athe bore is substantially circular in cross-section and in which `at least the portion of the spring bar member which is mounted in said bore isof corresponding cross-section.

21. A torque measuring wrench comprising a head member, a work-engaging member rotatably mounted with respect to said head member and having a portion provided with a bore. said bore extending in a direction transverse to the axis of rotation of said work-engaging member, an elongated spring bar member having one end thereofwsecurely mounted in said bore and having itsopposite end swivelly connected with said head member for yieldably opposing relative rotary movement of said head member and workengaging member, and indicator means operable as said head member and .work-engaging member rotate relative to each other for indicating the forceapplied to the work through said members and spring bar.

22. A torque measuring Wrench comprising', a head member, a work-engaging member rotatably/mounted with respect to said head member and having a portion provided with a bore, an elongated spring bar member having one end thereofy securely mounted in said bore and having its opposite end swivelly connected with said head movement of said head member and Work-en- .gaging member, indicator means, and flexible means operably connected with one of said mem-l bers and with said indicator means for actuating said indicator means to indicate the force applied to the work through said members and spring bar.

23. A torque wrench adapted for use with means for indicating the force applied to the ymember for yieldably opposing relative work comprising, a head member, a work-engaging member rotatably connected to said head member, an arm extending substantially radially from said Work-engaging member, said arm having a longitudinal bore extending from its outer end. toward the axis of rotation of said work-engaging member, an elongated spring bar yieldably opposing relative rotary movement of said head and work-engaging members, said spring bar having one end fixedly mounted in and extending substantially to the rear end of said longitudinal bore, means connecting the opposite end of said spring bar to said head member, said means being such as to permit pivotal movement of said spring bar'relative to said head member, and means operable upon flexing of said spring bar and consequent relative rotary movement of said headand work-engaging members for operating said "indicating means to indicate the force applied to the work.

24. A torque measuring wrench comprising a pair of members, one of said members being adapted to be connected with the work and the other of said members being adapted to have an operating force applied thereto, yieldable torque resisting means operatively connecting said members together arranged so that an operating force applied to said one member is transmitted to the other member to turn the work, the member adapted to be connected with the work including a portion that is rotatably movable relative to the other member by force applied l tothe work upon yielding'of said torque resisting means, indicator means carried by one of the members, and actuating means carried by the other of the members and being cooperable With said indicator means for effecting an indication of the force applied to the work in response to` said relative movement, said actuating means comprising a'normally unexed member having sufficient flexibility to absorb shocks caused by release of the Wrench when under operating stress, thus preventing injury to said indicator means.

25. A torque measuring wrench comprising a pair of members, one of said members being a. Work-engaging member adapted to be connected withthe work and the other of said members being a handle' member adapted to have a turning force applied thereto, yieldable torque resisting means operatively connecting said members together arranged' so that turning force applied to said handle member is transmitted to said work-engaging membei to turn the work, said work-engaging member including a part rotatably movable relative to said handle memvvberupon yielding of said torque resisting means in proportion tothe force applied to the work, indicator means carried by said handle member,

and flexible means carried by said part of said lwork-engaging member, said flexible means comprising a normally uniiexed member cooperable with said indicator means for effecting an indication of lthe force applied to the work, said lastmentioned member having suicient flexibility to serve as a shock absorbing means to prevent injury to said indicatorl means upon release of the wrench while under operating tension.

26. A torque wrench comprising: a handle member including an elongated body member having a chamber extending throughout substantially the full length thereof .and an elongated.

cover member adapted to be attached to said body member to form a closure for said chamber; indicator means carried by one of said members; a. work-engaging member having a portion in said chamber and being constructed so that it can be operatively connected with the work; a substantially rigid member in said chamber ilxed at one end thereof to said Work-engaging member and extending substantially radially `from said work-engaging member lengthwise of said chamber, a relatively flexible element carried by the opposite end of said rigid member, yieldable torque resisting means providing an -operating connection between said handle member and said shocks caused by release of the Wrench when under operating stress, thus preventing injury to said indicator means.

27. A torque Wrench comprising a casing member, a work-engaging member mounted in said casing member and displaceable relative thereto, means by which said work-engaging member may 4 be engaged with the Work, means on said casing member by which it may be moved, yieldable torque resisting means between and opposing relative displacement of said casing and workengaglng member, indicating mechanism carried by said casing member and including an indicating element and a movable operating part therefor, and coupling means secured at one end thereof to said work-engaging member, the opposite end of said coupling means being relatively free and having an element operably connected with said operating part for moving th latter as said casing and work-engaging members are displaced relatively, said coupling means having flexing ability in a direction parallel' with the direction of displacement of said casing and work-engaging members.

28. A torque wrench comprising a pair of members rotatably displaceable relative to each other, one of said members having an element adapted to be engaged with the work, the other of said members having a handle by which it may be moved, yieldable torque resisting means opposing rotative movement between said members, and

torque measuring means including a gage member on said member having the handle, said gage member having a movable gage operating part, a rigid arm connected to said member having the Work-engaging element, a flexible extension on said arm, and a coupling element on. said extension adapted to be operably connected to said operating part' for operation of said gage member as said members are rotatably displaced, said flexible extension servingto absorb shocks on said gage member. n

29. A torque measuring wrench comprising, a handle member, a work-engaging member, yieldable torque. transmitting means between said handle member and work-engaging member providing an operativev connection between said members for transmitting turning force from said handle member to said Work-engaging member, an indicator carried by one of said members for indicating the force applied to the work, and means for actuating said indicator operatively connecting the other of said members with said indicator, said indicator actuating means being movable transversely to said handle member and includingshock absorbing means for absorbing shocks which would otherwise be transmitted to said indicator when said wrench is released while under operating stress. said shock absorbing means being flexible in the direction o! movement j of said' indicator actuating means.

so. A torque measuring wrench as dennen in A claim 29. in which the shock absorbing means comprisesa normally unnexed bar.

31. A torque measuring wrench comprising'a pair ot Amembers rockably connected together.

means by which one of said members may be engaged with the work. means on the other o! said members by which it may be-moved.' spring l5 means yieldably Aoppi'ising rock movement between said members. sage mechanism carried by the one oi' said members having meensby which it may be moved, said gage mechanism including sn operating psrt movableback and forth, and coupling means carried by the one ot said members having means for engaging it with the work. said coupling means having an el ent adapted to receive said operating part for oving the latter back and forth as said members rock relatively and said coupling means being adapted'to' flex in the direction o! movement of said operating part. f i

h HERMAN W, Haart AN. 

